Juan Mata is convinced Manchester United teammate David De Gea can achieve greatness.
Mata won international youth honours for Spain with goalkeeper De Gea and he believes United's player of the year has the mentality to become an Old Trafford great.
"He has huge faith in himself, which is a really important virtue," Mata told the Daily Mail. "He doesn't let anything affect him. He knows if he has made a mistake but it never sinks him. He uses it to make sure that he doesn't make the same mistake next time. He's very calm."
